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Radiator brake fluid change

Discussion in 'Gen 4 Prius Care, Maintenance and Troubleshooting' started by jebcolpitts, Jun 14, 2024.

  1. jebcolpitts

    jebcolpitts New Member

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    2018 Prius 2 37,000 Miles: I just recently had my oil changed and tires rotated: The technician told me I needed to change out the radiator and brake fluid. Is this just up selling or could be true?
     
  2. Tideland Prius

    Tideland Prius Moderator of the North
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    Brake fluid replacement should've been done at 30,000 miles. Next one is at 60,000 miles.

    Engine coolant and inverter coolant is done at 100,000 miles.
     
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  3. BiomedO1

    BiomedO1 Senior Member

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    Check your service manual. I believe European service manuals specify every two or three years. In my experiences; I've bought and owned cars that was more than 10 years old - brake fluid never touched. Brake fluid failed testing. but still work fine. Flushed out the system while gauging pad & rotor wear - braking improved substantially. Your brakes won't TOTALLY fail if this isn't done. I would recommend testing the fluid to see if it needs changing - which should've been performed before recommending changing. If your shop performed the test and it passed, they recommend you change it. If it failed the test, a shop would/should make you sign a waiver before handing over the keys, because you knowingly refused brake work (safety issue) to cover the shop's assets.
    I believe US Toyota maintenance interval is simply a check, but you should double check what your manual states. That way you don't violate any remaining manufacturers or extended warranty you may have left on the car.

    Hope this helps....

    After looking up your zip code, You should probably get your coolant tested too. Your car is located in a harsh environment with major temperature swings. I'm in a more temperate climate which is easier on my cars overall. We rarely see 5 year old rust buckets out here. I once looked at a car from Pacifica, a town on the coast. Interior and exterior was well kept, popped the hood - everything was rust pitted, including the underside of the hood and inner fenders.
     
    #3 BiomedO1, Jun 15, 2024
    Last edited: Jun 15, 2024
  4. Kenny94945

    Kenny94945 Active Member

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    Yes, best advice follow your owner/ service manual/ schedule.

    FWIW.
    Brake fluid is hydroscopic: absorbs moisture.
    Many (many) recommend to change/flush brake fluid every 2 years.
    Coolant "wears" out.
    Some recommend changing every 6 (or so) years (like "red" Dexcool brand).
    FURTHER
    I personally recommend, regarding coolant, to flush and mix with distilled water, not "drinkable" or portable water.
    For the coolant, there are tools/ machines to evacuate the old coolant as opposed to draining, fill with 100% water, drain, and the final fill w/ coolant.
    I think to flush the brake fluid one needs to utilize a Toyota computer program (but there may be workarounds).
    I would not be surprised for both maintenance items the cost is $400 at a dealer.
    (Even at 35K mileage, then there is preventative maintenance for the transmission fluid/ oil.... yet that's another subject.)
    All are easy enough to DIY.
    IMO
    For the OP, I would change the brake fluid now, and check your manual about the coolant.

    Good luck.
     
  5. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    @jebcolpitts : that number in your location, it’s a United States zip code, you’re in California? If so:

    Toyota USA schedule says nothing about brake fluid change. FWIW, Toyota Canada says to change it every 3 years or 48k kms (30k miles), whichever comes first.

    For engine coolant, Toyota USA says to do first change at 10 years or 100k miles, and for the inverter coolant it’s 15 years or 150k miles. Again, FWIW, Toyota Canada says to do BOTH at the engine coolant interval. Also, a few DIY’rs advocate to do first changes at 50k miles. That is the subsequent interval for both, BTW.

    The Toyota USA maintenance schedule is in the Warranty and Maintenance Booklet, a copy of which comes with every US car. If it’s missing you can download PDF from Toyota Tech Info website for one.

    that publication is a very awkward, event-by-event format; I’ve made a table format spreadsheet conversion, can upload in a bit.

    something else to consider: transaxle fluid change. Stick with Toyota ATF WS fluid for that.

    Is your mechanic an independent? If you want I can upload repair manual info on the above.
     
  6. BiomedO1

    BiomedO1 Senior Member

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    His zip code indicates he's in Maine.
     
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  7. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Ah, thanks. I saw Oakland, jumped to California. :oops:
     
  8. Doug McC

    Doug McC Senior Member

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    Brake fluid degrades over time due to anti-corrosion additives degrading, and also absorbing moisture. This can lead to failures of various components which can be expensive. You can test it yourself or have it tested. If the test shows signs of corrosion, have it changed, or ignore it and risk damage to the system. Your choice.
    Same thing with the coolant.
    As far as just following the service schedule recommendations, you will notice that the schedule DOES require testing of both and then changing if those tests indicate the need to. But most just ignore that part of the schedule.
     
  9. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    I just searched a pdf format Toyota USA Warranty and Maintenance Booklet: the expression "brake fluid" is not in it. The expression "check and adjust all fluid levels" is present, very regularly, but I can't see that being specific to a brake fluid change.

    Again, Toyota Canada does spec a brake fluid change interval.

    I've DIY'd the brake fluid change, a couple of times now. You do need to be on your toes but it's not that difficult. There is a non-Techstream procedure in the Repair Manuals, for both gen 3 and 4. More info in my signature (on a phone turn it landscape to see signatures).
     
    #9 Mendel Leisk, Jun 16, 2024
    Last edited: Jun 16, 2024
  10. BiomedO1

    BiomedO1 Senior Member

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    From what I've noticed at dealerships, whenever something in the maintenance manual states check - they interpret it as "check" the box. It may just be me, but the majority of dealer techs don't test - they just guess at the problem.
    I had an intermittent alternator issue on my old Acura. Drove 75 miles in the dark with my headlights going dim then brightening up again. The cycle would continue until I pulled into the next large city with a dealership. Decided to pack it in for the night, dropped it off at the dealership and checked into a motel. The dealership tried to tell me it was just a bad battery. Told the service manager, I drove 75 miles at night with the alternator functioning intermittently - of course it isn't going to pass a battery test - re-read my problem description. I'll be there in an hour - after breakfast. Dealership claimed that they tested the alternator output and it was fine; so I made them waive the tow-in diagnostic fee and paid for a new battery, but made them put in writing that if this doesn't solve my issue they will credit me this repair cost. I got maybe a block before the alternator light blinked back on. Turned the car around and dragged the service manager out to my car, showing him the alternator lamp is on again (alternator lamp is a battery symbol). Told the manager to get this technician over here with his battery and alternator test equipment. Technician showed up w/o any test equipment. When pressed he still claimed he tested it, so I asked him what's the minimum amp output as the car sits here now - he didn't know, so I asked how do you test when you don't even know the hi - low parameters of the test? I went into my trunk, grabbed my meter and showed them the current output, battery voltage and told them to go look it up. Alternator was covered under warranty and battery replacement charges was reversed. I still wasted a half a day there for 1.5 hour job.
     
    #10 BiomedO1, Jun 16, 2024
    Last edited: Jun 16, 2024
  11. Robert21PrimeLTD

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    BREAK FLUID: I have been told by many automobile service providers (dealers and independents) that they recommend flushing and replacing the brake fluid on a regular basis. When I ask why, they all said that the fluid absorbs moisture. I'm not sure how that would happen on a totally closed system. I have owned a variety of cars for over 60 years and have NEVER flushed or replaced brake fluid and have never had a problem. I've always viewed this as a profit making item for the shop.

    Have I been lucky or just cheap?
     
  12. BiomedO1

    BiomedO1 Senior Member

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    A little bit of both. Old cars was built like tanks, lots of metal, mainly because we didn't have the tools, know how, and ability to create cars affordability in bulk. Now we have plastic intake manifolds and composite materials. These new materials aren't going to put up with the abuse we used to dish out on our old cars. IMHO.

    A brake fluid moisture tester is $6 - $12 on Amazon.You get moisture and air seepage through the brake fluid reservoir cap, so not an entirely closed system (see #3). Contaminants build up through heat and cold cycling of the system, wear and tear on the seals, and simple chemical break down.